This invention relates in general to force applying devices and methods and in particular, to an improved measuring bridge for use in an apparatus for straightening and reforming vehicle bodies and frames.
More specifically, the invention relates to an apparatus for straightening reformed vehicle bodies, frames and other parts of damaged or misaligned vehicles wherein a measuring bridge of the apparatus is positioned in coupling relationship to a vehicle to be straightened. The measuring bridge is oriented for use by a plurality of vertical elements which are adapted to be secured to a plurality of datum locations positioned in undamaged portions the vehicle body. The measuring bridge is maintained in proper orientation by restraining the plurality of vertical elements from movement relative to the measuring bridge.
In addition, other vertical elements are attached to datum points in damaged portions of the vehicle whereby the base of each vertical element is movable in two perpendicular directions laterally and longitudinally of the vehicle and the vertical element is also vertically extendible. The initial position of each datum point and its progress to a proper position to attain symmetry of the vehicle is continuously measured. The measuring bridge is maintained in proper vertical position relative to the vehicle by air cylinder means which biases it against the vehicle by a predetermined force.
Reference is specifically made to the co-pending application of Bayorgeon, et al., Ser. No. 680,146, filed Apr. 26, 1976, now U.S. Pat. No. 4,055,061, for an Apparatus for Reforming and Straightening Vehicles in which there is disclosed an improved apparatus for straightening vehicles. Although the apparatus disclosed in the co-pending application produces significantly improved straightening accuracy over the prior art devices, the apparatus disclosed therein does not achieve an optimum degree of accurate orientation and reference to a vehicle to ensure maximum results when performing a straightening or reforming operation upon a vehicle body.
The achievement of optimum orientation of the measuring bridge of a straightener insures that the bridge is accurately situated relative to the vehicle body so that the reforming operation can be performed to achieve a degree of accuracy in realignment, reforming and straightening not heretofore possible.
In the straightener of the type disclosed in co-pending application, Ser. No. 680,146, now U.S. Pat. No. 4,055,061, a unique measuring bridge is utilized in which vertical elements are attached to datum points of a vehicle and the vertical elements are freely movable on the measuring bridge laterally and longitudinally and are vertically extensible whereby reforming operations may be performed on the vehicle and the vertical members continuously indicate whether datum points on the vehicle to which the elements are connected have returned to their proper position in accordance with the symmetry of the vehicle being straightened. Such an improved straightener provides a continuous and accurate three dimensional indication as to whether the datum points have returned to target positions which are unique in each model vehicle indicating that a proper corrective reformation of the vehicle has been achieved.
To improve the unique technique of straightening and reforming vehicles as described in the previously mentioned co-pending application, it is desirable to maximize the accuracy of the referencing and orientation of the measuring bridge relative to the vehicle initially and during the application of force to provide the greatest possible results.